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| <?php
function binarySearch($arr, $item) { $low = 0; $high = count($arr) - 1; while($low <= $high) { $mid = floor( ($low + $high) / 2 ); if($arr[$mid] == $item) { return $mid; } elseif($arr[$mid] < $item) { $low = $mid + 1; } else { $high = $mid - 1; } } return -1; }
function binary($arr, $item, $low, $high) { if($low <= $high) { $mid = floor( ($low + $high) / 2 ); if($arr[$mid] == $item) { return $mid; } elseif($arr[$mid] < $item) { return binary($arr, $item, $mid + 1, $high); } else { return binary($arr, $item, $low, $mid - 1); } } else { return -1; } } $list = [1, 2, 3, 4, 5, 6, 7, 8, 9]; $data = binarySearch($list, 3); echo $data; echo "\r\n"; $data1 = binary($list, 3, 0, count($list) - 1); echo $data1; echo "\r\n"; ?>
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